Since there are many different types of fiber connectors have been developed, we will talk about fiber optic connector in fairly general terms.
Most popular connectors in use today have some common elements. Let's examine it below.
The most critical part, where the fiber is mounted, is the ferrule. Ferrule is a long, thin cylinder with the fiber mounted in the center hole. The center hole is sized to match fiber's cladding diameter which is usually 125um.
Fiber connector ferrules are made from several types of materials including ceramic(Zirconia), stainless steel and plastic. The ferrule's job is to center and align the fiber and protects it from mechanical damage. The end of fiber is at the end of the ferrule, where the fiber end is polished smooth either flat or with a curvature.
Fiber optic inspection microscopes are used to inspect the end face of a optical connector or cleaved fiber. Two types of fiber optic microscopes are popular on the market: fiber optic connector termination inspection and fiber patch panel ferrule inspection. Magnification levels of fiber scope are available at 200X or 400X for single mode fiber applications, 100X low cost type for multimode applications. The latter is often included in many fiber optic termination tool kits.
What types of flaws or contamination can the microscope see?
With at least 200X magnification you can clearly see scratches, dig, dirt deposit, debris and other contamination on a fiber optic connector.
Desktop video fiber microscope
The typical desktop fiber optic video inspection microscope has a 9" black and white monitor attached to the scope with a 4 feet video cable. So you can place the monitor where it is convenient. Because of its bulk volume, this type of fiber microscope is typically used in production environments and labs. Both 200X and 400X versions are available.
Portable optical fiber scope
This type of microscope with universal adapter is a versatile instrument to inspect fiber optic connectors. They can be used for both multimode and single mode applications. Connectors slide into scope adapter, providing ease of use with or without tripod. 8° angle adapter can be used for inspecting angled connectors such as FC/APC, SC/APC, etc. Both 200X and 400X versions are available.
Coaxial Illuminated handheld fiber inspection scope
These low cost microscopes are available in 200x or 400x magnification, and utilize white LED light to provide coaxial illumination to connector end-faces. This method of illumination produces high resolution detail of end face scratches, defects and contamination. It is provided with a universal 2.5mm adapter, with other common connector styles available. These are the natural choice for fiber installation contractors.
Ferrule inspection microscopes
All aforementioned four types of microscopes are for standalone fiber connector inspection. But what about the connectors already installed on patch panels and hardware devices? The ferrule inspection microscopes are the solution.
These video fiber optic microscopes include a handheld LCD display unit and a small, lightweight probe that contains a long-life LED light source and CCD video camera. The probe adapter tip mates with the connector and projects a crisp, clear image of microscopic debris and end-face damage on the LCD display.